Description
Mattermost versions 10.5.x <= 10.5.6, 10.8.x <= 10.8.1, 10.7.x <= 10.7.3, 9.11.x <= 9.11.16 fail to verify authorization when retrieving cached posts by PendingPostID which allows an authenticated user to read posts in private channels they don't have access to via guessing the PendingPostID of recently created posts.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Mattermost Mattermost
Default version status: unaffected
10.5.0 to ≤ 10.5.6affected10.8.0 to ≤ 10.8.1affected10.7.0 to ≤ 10.7.3affected9.11.0 to ≤ 9.11.16affected10.9.0unaffected10.5.8unaffected10.8.2unaffected10.7.4unaffected9.11.17unaffected